The usefulness of D-dimer in diagnosis and prediction of venous thromboembolism in patients with abdominal malignancy

The aim: of the study was to evaluate the usefulness of D-dimer evaluation in the diagnosis and prediction of venous thromboembolism (VTE) of lower extremities in patients operated on for abdominal tumors depending on the chosen cut-off point for this parameter. Material and methods: We included 150 patients operated on for abdominal cancer in our department between October 2014 and June 2016. In these patients, concentration of D-dimer was determined, medical histories were taken, and physical examinations were performed. Ultrasound exams of the veins of the lower limbs were performed three times in every patient in order to confirm or exclude VTE. Results: When a standard cut-off point (500 ng/ml) was used, in 46% of cancer patients D-dimer values were elevated despite the lack of VTE. We did not detect any influence of cancer stage on the value of D-dimer. However, if cut-off point was 1440 ng/ml, which has been suggested in the literature, only 14% of patients were false positive. When the upper cut-off value for D-dimer was raised, the effect of cancer stage on the value of this parameter could be seen. Conclusion: The concentration of D-dimer is often elevated in patients with active cancer, but is not a sufficient criterion for diagnosis of VTE. The concentration of D-dimer before surgery does not determine the risk of postoperative thromboembolic complications. This is undoubtedly related to the widespread use of effective thromboprophylaxis. According to the literature, ultrasound is the optimum method for detection of VTE in surgically treated cancer patients. The effect of cancer stage on the value of D-dimer is revealed only when the cut-off point in this group is 1440 ng/ml, instead of 500 ng/ml which is used for the general population